Growth and biomass accumulation of a plant is dependent on photosynthetic CO2 assimilation. Ribulose-1,5-bisphosphate (RuBP) carboxylase/oxygenase (Rubisco) is the first enzyme involved in the conversion of CO2 into carbohydrates and its activity often limits plant photosynthetic rate. Many environmental changes, such as light intensity, temperature and drought can influence photosynthesis by affecting Rubisco performance.
Detection of RuBP and 3-phosphoglycerate (PGA) has been previously described by Whitney, S. M and Andrews, T. J (Plant Physiol. 2003, 133:287-294) and Cen, Y-P and Sage, R. F. (Plant Physiol. 2005, 139:979-990). In both publications the quantification of RuBP was coupled with Rubisco carboxylation of RuBP with 14C detection or NADH oxidation at 340 nm in a downstream reaction. PGA was assayed in coupled enzymatic assay and monitored at 340 nm for oxidation of NADH. Chakrabarti, S et al (J. Biochem. Biophys Methods, 2002 52:179-187) reported a detection and quantitation method for both RuBP and PGA based on a thin-layer chromatographic method. The major limitations of the current assays are low sensitivity and low throughput. There are no published methods that describe the direct, simultaneous detection and quantification of 2-phosphoglycolate (2-PA) with RuBP and PGA in planta.
For these and other reasons, there exists a need for the present invention.